is a solution of hydrogen fluoride in water. Together with hydrogen fluoride, hydrofluoric acid is a valued source of fluorine, being the precursor to numerous pharmaceuticals, diverse polymers (e.g. Teflon), and most other synthetic materials that contain fluorine. Hydrofluoric acid is best known to the public for its ability to dissolve glass by reacting with SiO2, the major component of most glasses. This dissolution process can be described as follows:
Solutions of less than 20% HF can produce pain and redness with delay up to 24 hours after skin exposure. 20 to 50% HF produces pain and redness within 8 hours, and solutions of more than 50% produce immediate burning, redness and blister formation. Contact of the skin with the anhydrous liquid produces severe burns
- Consult an ophthalmologist immediately in all cases.
- Take to a hospital immediately.
- Flush eyes as soon as possible with running water for 15 minutes, while keeping the eyelids wide open.
- Rinse the eyes with calcium gluconate (1% solution in physiological serum) (10 ml of calcium gluconate 10% in 90 ml of physiological serum).
- In case of difficulty opening the lids, administer an analgesic eyewash (oxybuprocaine).
A case of fluoride poisoning of a girl aged 2(1/2) years is reported. "Although the possibility of ingestion was originally denied by the mother, repeated questioning revealed that prior to becoming ill the child had been playing with a laundry powder. The mother had obtained this material from a commercial laundry. The powder was identified as "Bayline Brand Laundry Sour" (manufactured by BASF Wyandotte, Michigan), a whitener sold only to commercial laundries. This contained sodium silico fluoride (Na2SiF6) as its major ingredient ..."
Ammonium fluoride, [NH4]F, may be obtained by neutralizing ammonia with hydrofluoric acid. It crystallizes as small prisms, having a sharp saline taste, and is exceedingly soluble in water.
KF or KF·2H2O Poisonous, white, deliquescent crystals with saline taste; soluble in water and hydrofluoric acid, insoluble in alcohol; melts at 846°C; used to etch glass and as a preservative and insecticide.
Sodium fluoride is the inorganic compound with the formula NaF. This colorless solid is a source of the fluoride ion in diverse applications. Sodium fluoride is less expensive and less hygroscopic than the related salt potassium fluoride.